This invention relates to optical disk apparatus used with replaceable optical disks each accommodated in a cartridge and, more particularly, to a method of controlling the cleaning of the optical head or the like of such optical disk apparatus, in which a cleaning request is made to an upper order apparatus under control of cleaning time.
In a prior art optical disk apparatus used with read-only optical disks or rewritable optical magnetic disks, a laser is used for reading and writing information. In such optical disk apparatus, an object lens converges a laser beam to be projected and focused on a recording film of a rotating optical disk. However, if the apparatus is used for reading or writing without cleaning for long time, a window, through which the objective lens is exposed to the outside, is contaminated by dust and result in read or write errors. More specifically, in the write operation dust reduces the light intensity of the emitted beam to result in insufficient writing of information on the optical disk, thus generating verify errors. In the read operation, dust reduces the light intensity of both emitted and returned beams to result in insufficient reproduced signal amplitude, thus generating read errors. Accordingly, it is required to control the cleaning of the optical head of the optical disk apparatus.
Heretofore, it has been prescribed to carry out the cleaning of the optical head and other optical components of the optical disk apparatus periodically, and it is done by the user or maintenance personnel. Where the cleaning is done periodically, however, the extent of contamination of the optical part of the apparatus varies with the circumstances of use of the apparatus. Therefore, if the apparatus is used frequently, read or write errors may be generated by dust before the periodic cleaning. Further, in the event the periodic cleaning is neglected, read and write errors are generated without any known cause, making it necessary to call maintenance personnel for inspection.